In recent years, Internet has been widely employed worldwide. In particular, the World Wide Web (WWW) portion of Internet can provide voice, graphics, and multimedia services in addition to e-mail transmission and receiving. Hence, people can access a variety of information from WWW. Further, many people take log-on the Internet as a daily work. For accommodating such trend, a variety of high speed network devices have been provided by network equipment manufacturers. Such devices comprises cable modem, asymmetric digital subscriber line (ADSL), etc. Moreover, various associated network peripherals are provided by network equipment manufacturers for enhancing the functionality of network. Such peripherals comprises voice over IP device (VoIP), etc. User can employ VoIP to communicate with a remote user over the Internet so as to greatly reduce long distance or international telecommunication charge.
Current network structures may be broken down into the following three broad categories based on a connection between end user and the Internet:
(1) ADSL based network structure. A connection of the ADSL based network is shown in FIG. 1. An Ethernet NIC 10 at end user comprises an ADSL communication interface 11 and a router control circuit 12 coupled to an exchange 14 through a telephone line 13 for transmitting ADSL (or ATM) packet signals thereto or receiving the same therefrom. Exchange 14 also transmits generated ATM packet signals to the Internet 15 (or receives ATM packet signals from the Internet 15) through a fiber-optic line 131 connected therebetween by utilizing ATM network structure thereof. The transmission rate is about 640K byte per second while uploading or about 1.5M byte per second while downloading with the provision of fiber-optic line 131 as packet transmission medium. However, its cost is inhibitory high for ordinary network users since it is required to install the high speed ATM network in the exchange. Hence, the ADSL based network structure is rarely implemented.
(2) Cable modem based network structure. A connection of the cable modem based network is shown in FIG. 2. As shown, a plurality of Ethernet network interface cards (NICs) 20 each is coupled to one of a plurality of cable modems 201 which is further coupled to a node 22 in a community installed by a cable TV company (or network services provider or exchange) through cable 21. Node 22 is in turn coupled to a network equipment 24 provided by cable TV company through a fiber-optic line 23. Network equipment 24 is also coupled to the Internet 25 through fiber-optic line 23. Hence, packets signals may be sent from Ethernet NICs 20 to the Internet 25, or alternatively Ethernet NICs 20 may receive packet signals from the Internet 25. In this network structure, node 22 in a community installed by a cable TV company may utilize the high speed fiber-optic line 23 to send signals to about 100 to 500 end users in a typical community through cable 21 of cable TV company. This can increase transmission rate of signals between end users and the Internet. Hence, such cable modem based network structures only have been employed in communities having cable TV services. Typically, a cable TV company may utilize a single fiber-optic line for transmitting packets including management and data packets in managing nodes installed by a cable TV company in communities. Hence, such network is subject to intrusion by hacker. This is a management drawback.
(3) Unshielded twisted pair (UTP) based network structure. A connection of the UTP based network is shown in FIG. 3. A plurality of Ethernet NICs 30 at end users each also comprises an ADSL communication interface 11 (not shown) and a router control circuit 12 (not shown) coupled to an Ethernet switch 32 installed in a community by an exchange (or network services provider) through an existing UTP telephone line 31. Ethernet switch 32 is in turn coupled to an Ethernet equipment 34 provided by exchange through a fiber-optic line 33. Ethernet equipment 34 is also coupled to the Internet 35 through fiber-optic line 33. Hence, packets signals may be sent from Ethernet NICs 30 to the Internet 35, or alternatively Ethernet NICs 30 may receive packets signals from the Internet 35. In this network structure, Ethernet switch 32 in a community installed by the exchange may utilize the high speed fiber-optic line 33 to send signals to a predetermined number of end users in a typical community through existing UTP telephone line 31. This can increase transmission rate of signals between end users and the Internet. Hence, such UTP based network structures have been widely employed in local networks of communities. Typically, management of the network is performed in an online manner since there is a considerable distance between Ethernet switch 32 in a community and the exchange, thus inhibiting an on-the-site network maintenance and management. Further, such online technique is restricted by a simple network management protocol (SNMP), thus inhibiting a real time online maintenance and management on Ethernet switch by the exchange. Instead, maintenance personnel has to go to the site of Ethernet switch for maintenance. This has the drawbacks of increasing management cost, lowering network service quality, and many more. Thus improvement exists.